The dramatic impact of potent combination antiretroviral therapies on the course of HIV disease has made the use of PIs routine in the care of HIV-1-infected individuals. Combination therapy likewise has become the standard of care in pregnant individuals, even though information on use of these drugs during human pregnancy is limited. There are no published prospective evaluations of toxicities experienced by pregnant women on PI-containing antiretroviral regimens, despite findings of metabolic disturbances of glucose, fatty acids, and cholesterol, as well as lactic acidosis/hepatic steatosis in nonpregnant individuals treated with antiretrovirals. Gastrointestinal (GI) side effects also are well documented in nonpregnant individuals treated with PIs, but have not been systematically evaluated in pregnancy. In addition, the physiologic changes brought about by pregnancy may influence the pharmacokinetics, safety, and side effects of antiretroviral drugs. There remains a need for further evaluation of the use of antiretrovirals during pregnancy and their impact on maternal, fetal, and infant safety.